反应pH值对微波法合成的Mo修饰的Pt/C催化剂结构和乙醇电氧化催化性能的影响

通过调节微波反应溶液的pH值合成了一系列Mo修饰的Pt/C催化剂并用于乙醇的电氧化催化反应.利用X射线衍射(XRD)、透射电子显微镜(TEM)及X射线光电子能谱(XPS)对催化剂的晶型结构、微观形貌、粒径尺寸和表面电子结构进行了表征,并采用循环伏安法(CV)、计时电流法(CA)和电化学阻抗谱(EIS)对催化剂的乙醇电氧化催化性能进行了测试.结果表明,碱性环境有利于催化剂组分在碳载体上的均匀分布,pH值为14时制得的催化剂组分颗粒尺寸最小,且分布最均匀.该催化剂不仅表现出了最大的有效电化学比表面积和最高的乙醇电氧化催化活性,而且具有最稳定的乙醇氧化催化性能.

Effects of pH on the Properties of Mo-Modified Pt/C Synthesized by Microwave-Assisted Method as Catalyst for Electro-Oxidation of Ethanol

A series of Mo-modified Pt/C catalysts were synthesized, using a microwave-assisted technique, and the effects of pH value on the electrocatalytic performance of the resulted catalysts for ethanol oxidation were investigated. X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) were employed to characterize the crystal structures, morphologies, particle sizes and the distributions, and electronic states of the catalysts. Cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) were used to investigate the catalytic performances. The results revealed that alkaline environments are beneficial in the syntheses of catalysts with small and uniformly dispersed particles on the carbon support. The catalyst prepared at pH 14 exhibited the smallest catalyst particles, highest electrochemical surface area, best electrocatalytic activity, and durability for ethanol oxidation.